In recent years there has been a development from traditional mechanical keys to electronic keys. Electronic keys can be active, such as the IR key traditionally used to unlock cars, or such as some NFC based systems. In alternative embodiments, the electronic keys may be passive, such as magnetic cards, barcode cards, RFID based systems, or fingerprint based systems.
The electronic keys listed above all have one thing in common, and that is that they require the user to be active. In the example with a magnetic or bar code card, this card needs to be swiped in a reader, in the example with an RFID or NFC based system, the card or tag needs to be placed in front of a reader, and in the example with fingerprint based systems, the finger of the user needs to be placed on some form a fingerprint scanner.
The active step that is performed by the user ensures that the intention of the user is to unlock the lock connected with the electronic key. Hence, as the unlocking involves an active step, the risk that the user will unintentionally unlock the lock is very low.
In some applications where a lock is needed, the person that should use the lock may be unable to perform the active steps that these devices require. Such applications could for example be when the person is mentally or physically disabled. Additional considerations that includes the fact that some locking systems are slow and thus requires some time to fully unlock door, and the fact that some locking systems consumes a lot of power in operation, which may be a drawback in battery operated system.
There is thus a need for an electronic key which does not require the active step by the user, while at the same time ensuring that the intention of the person is to lock or unlock the locking mechanism operated by the electronic key.